T-611 GENERAL PROCEDURE FOR REPLACING EPROMs (FIRMWARE)

The EPROM used in the T-611 Reader Unit comes as a 32 pin PLCC package without a window. It sits on the printed circuit board in a special 32 pin socket. This integrated circuit is the chip that contains the program used by the Reader Unit. 

To replace the EPROM with a new one carry out the following steps: 

1. Ensure that the T-611 is turned OFF.
2. Unplug the sensor connector.
3. WARNING: The EPROM's and the circuit board are electrostatic sensitive, so standard precautions for handling CMOS devices should be followed. This includes not touching the pins of the EPROMs.
4. Place the Reader Unit face down and disassemble the T-611 front panel from the case by removing the 4 stainless steel retaining screws. The panel may need to be levered with a screwdriver to release the seal. Unplug the cables that connect on the circuit board (this circuit board is mounted on the inside of T-611 Reader Unit front panel).
5. The EPROM in the socket on the circuit board should now be removed. Care should be taken when removing and inserting this chip so that no pins are bent. If you don't have a special tool, it is  possible to very delicately and gradually lift the chip out of its socket with a thin precision screw driver, working your way around the corners bit by bit. Put the EPROM in an electrostatic safe location.
6. Insert the new EPROM in the socket. The chip should be oriented such that the corner indent on it is aligned with the corresponding indent on the socket. Take special care to ensure it goes in straight and smoothly.
7. Reconnect the cables to the circuit board. Screw down the front panel onto the Reader Unit case.
8. Connect the sensor probe to the connector on the Reader Unit.
9. Hold down ESC key and switch ON. The display will ask RESET? Press ENTER. The display will ask if depth sensor is installed. Press ENTER if one is installed. The unit is now reset. 

The T-611 should function normally.